Island



(No Model.)

W. D. PORTER.

I DENTAL FILLING. No. 488,634. Patented Dec. 27, 1892.

UNITED STATES PATENT ()rrrcn.

WILLIAM D. PORTER, OF PROVIDENCE, RHODE ISLAND.

DENTAL FILLING.

SPECIFICATION forming part of Letters Patent N0. 488,634, dated December 27, 1892.

Application filed May 20, 1892- fierialNo. 433.748. (No model.)

To all whom it may concern.-

Be it known that I, WILLIAM D. PORTER, of the city and county of Providence, in the State of Rhode Island, have invented a certain new and useful Improvement in Compound Gold Filling for Dentists Use; and I declare the following to be a specification thereof, reference being had to the accompanying drawings.

Like letters indicate like parts.

Figure 1 represents in plan view a piece of gold foil and a strip of plastic gold thereon. Fig. 2 is a perspective view of said strip of plastic gold wrapped in the gold foil. Fig. 3 is a transverse section of a pellet of my improved filling on the line a: w of Fig. 2. Fig. 4 is a longitudinal section of said pellet on line 2 z of Fig.2.

Myinvention consists of a mechanical combination of finely granulated gold, wrapped in one or more layers of gold foil, inserted into the cavity of a tooth and compacted therein by suitable instruments, as hereinafter particularly specified.

In filling cavities in teeth, dentists have heretofore commonly used thin sheets of beaten gold, commercially called gold foil, which are cut or torn in pieces of suitable size, rolled into small masses and compacted in the cavity by pluggers or other proper instruments. The cavities made for such filling must be very carefully prepared by excavating the dentine with proper under-cuts and retaining points and are made of a considerable depth to properly receive and retain the filling. In the form of afoil or thin sheet, the gold retains its ductility and when rolledor massed has great malleability, butit also has a certain degree of elasticity or a tendency to spring back from the blow of the compacting instrument. For this reason, gold fillings thus made sometimes cleave from the walls of the cavity, or have a rocking motion within the cavity, which makes the operation more tedious to the patient and requires great skill on the part of the dentist.

Another form in which gold is prepared for dentists use is that commercially known as plastic gold, or mat gold, and which is produced by the precipitation of a gold solution or by electrolysis. This is a form of unbeaten gold and is soft and devoid of elasticity, but being granular in its composition easily crumbles and lacks cohesiveness and tenacity. It however fills the cavity more perfectly, and when under the pressure of the instrument does not recoil or creep away from the sides of the cavity, but has a tendency to spread laterally and fill the space sidewise. But it is a more expensive form of gold filling than the gold foil and on account of its brittleness and crumbling nature, its use is accompanied with considerable Waste, as the fragments taken up by the forceps are liable to break before they can be conveyed to the tooth.

My invention consists in using both these forms of gold in combination. For this purpose I cut a sheet or strip A of gold foil and taking a fragment or strip B of the plastic gold of the desired size, I Wrap said fragment or strip B in the strip or sheet A of the gold foil. I fold or roll the strip or sheet of gold foil over the plastic gold one or more times and then by scissors cut the roll crosswise as for example, on the lines indicated by dashes in Fig. 2 to form smallmasses or pellets suitable to introduce into the cavity. The cross cuts by reason of the great ductility of the gold press the gold foil down into and through the granular gold and close the ends of the section by bringing together the severed edges of the foil thus forming a tip which is an advantageous shape for the insertion of the gold into the tooth.

The gold foil Wrapper serves as a vehicle to carry the plastic gold without crumbling, thus preventing Waste.

The compound filling so formed combines the favorable qualities of both forms of the gold and obviates the unfavorable qualities of each. The section or mass thus formed has all the softness of the plastic gold and all the tenacity and ductility of the gold foil, while it cannot crumble and has no elasticity whatever. It spreads out from the instrument in the lateral directions and fills every crevice of the cavity. It has no tendency to cleave from the tooth or to follow the instrument back and when compacted by the repeated blows of the plugger, it becomes a homogeneous mass, in which the granulation wholly disappears and the two kinds of gold cohere perfectly. On account of these admirable qualities, a less extent of excavation is necessary and less deep under-cuts and fewer retaining points'are required. The patient is consequently spared much pain; a larger portion of the bodyof the tooth is saved and less skill is needed in the preparation of the cavity. The compacting of the gold is more quickly and satisfactorily accomplished. The metal is soft and plastic and readily adapts itself to the cavity. The inelasticity of the substance permits more rapid work and all tendency to creeping or rocking is prevented. When compactedthe filling-is more 3 solid than gold foil filling. It has fewer pits or marks of the plugger points.

The plastic gold can be much better an- 15 nealed if protected and covered by the foil wrapper, in cases where annealing is desired.

I claim as a novel and useful invention and desire to secure by Letters Patent,

Theimproved compound gold filling pellet 20 for dentists use herein described, consisting of a piece of plastic gold inclosed in a wrapper of gold foil, substantially as specified.

WILLIAM D. PORTER. Witnesses:

HARMON S. BABCOOK, WARREN R. PEROE. 

